1. Field of the Invention
This invention relates generally to the field of System-on-Chip (SoC) security, and more specifically to implementation of one time programmable memory using embedded flash memory on an SoC.
2. Description of the Related Art
Increasingly, sophisticated hardware systems are implemented on single computer chips. Such a system is referred to as a System-on-Chip (SoC). An SoC generally includes at least one controller and memory, and is generally required to perform auxiliary functions for the system, such as initialization and reset functionality. Moreover, many of these systems include security features that utilize one time programmable (OTP) memory that cannot be reprogrammed or erased. Because OTP memory cannot be modified (after its initial programming), it is suitable for such security functions.
Flash memory, in contrast, can be erased. If an SoC requires a large flash memory, adding OTP can increase costs, since OTP typically requires different processing in manufacture than flash memory, as well as additional area. However, as currently used, flash memory can be erased, which means it cannot be used for security functions, since an attack could erase the flash memory, thereby eliminating the security function.
Other corresponding issues related to the prior art will become apparent to one skilled in the art after comparing such prior art with the present invention as described herein.